
public class MyTimeSub 
{
	private int hour;
	private int minute;
	private int second;
	public MyTimeSub()
	{
		this.hour=12;
		this.minute=25;
		this.second=40;
	}
	public void subSecond(int second)
	{
		this.second-=second;
		if(this.second<=0)
		{
			subMinute((Math.abs(this.second)/60)+1);
			this.second=60-Math.abs(this.second);
		}
	}
	public void subMinute(int minute)
	{
		this.minute-=minute;
		if(this.minute<=0)
		{
			subHour((Math.abs(this.minute)/60)+1);
			this.minute=60-Math.abs(this.minute);
		}
	}
	public void subHour(int hour)
	{
		this.hour-=hour;
		if(this.hour<=0)
		{
			this.hour=24-Math.abs(this.hour);
		}
	}
	@Override
	public String toString() 
	{
		return hour + ":" + minute + ":" + second;
	}
}
